Field
The present disclosure relates generally to electronic apparatus with circuits, and more particularly, to electronic apparatuses with token-based power-switch control circuits.
Background
A typical electronic apparatus, such as a processor within wireless devices, may include various cores and power domains. A core may vary from a collection of transistors or circuits to a processor execution unit. Each of the cores may be powered by a power switch. An example of a power switch may include a transistor coupled to a power rail of a power domain and controlled to selectively provide power from the power rail to a core.
Increasingly, the cores are powered down and then powered up at various times to save power. When too many cores power up at the same time they draw too much power from the power rail, and the voltage in the power domain may drop. One design challenge is to power up the cores in a manner that does not draw too much power at once so as not to collapse the power domain.